Backed out 6 changesets (bug 1816934, bug 1817182, bug 1817179, bug 1817183)...

Backed out 6 changesets (bug 1816934, bug 1817182, bug 1817179, bug 1817183) for causing dt failures in browser_jsterm_autocomplete_null.js CLOSED TREE

Backed out changeset 17d4c013ed92 (bug 1817183)
Backed out changeset cfed8d9c23f3 (bug 1817183)
Backed out changeset 62fe2f589efe (bug 1817182)
Backed out changeset 557bd773fb85 (bug 1817179)
Backed out changeset 7f8a7865868b (bug 1816934)
Backed out changeset d6c1d4c0d2a0 (bug 1816934)